Hey there,
Please could you see this https://us.forums.blizzard.com/en/overwatch/t/skins-missing-or-becoming-locked/1566 for as much information as possible.
Direct Link to topic is
here, click to expand
I also tried to share this over on Reddit but no activity yet unfortunately and I don’t fully understand that site: https://www.reddit.com/r/Overwatch/comments/7ydf9r/missing_or_locked_cosmetics_etc/
There is one thing I would like to mention that I can’t remember if I wrote about in my documentation. But that is charge backs that normally occur to loot boxes.
Now I’m not an expert on this, I just know that sometimes after loot boxes are purchased there could be an issue with payments processing or other similar causes. Which prompt a charge back.
As a result of this any unlocked items or credits earned from that batch of loot boxes will vanish or become locked again if a charge back occurs.
To my knowledge this is one of the common causes for negative amount of credits.
I’m not sure but you may have the loot boxes themselves returned or a refund when this event occurs, but that is just my speculation as I do not know for certain.